Effects of HBO2 on phase and morphology of ZrB2 powders synthesized by carbothermal reduction

Abstract Zirconium diboride (ZrB 2 ) powders were synthesized by carbothermal reduction with ZrO 2 , HBO 2 , and carbon black as raw materials. The effects of reaction temperature and HBO 2 content on the phase and morphology of ZrB 2 powders were investigated. The phase composition was characterized by X-ray diffraction (XRD) and the micromorphology was observed by scanning electron microscope (SEM). The thermodynamic reaction process was studied. When the amount of HBO 2 was 60 wt%, pure ZrB 2 powders could be obtained, as indicated by XRD results. Hexagonal ZrB 2 particles ranging from 1 to 2 µm could be successfully prepared at 1600 °C in Ar atmosphere while adding 30 wt% NaCl.